We report the discovery of a giant planet in the OGLE-2017-BLG-1522 microlensing event. The planetary perturbations were clearly identified by high-cadence survey experiments despite the relatively ...short event timescale of tE ∼ 7.5 days. The Einstein radius is unusually small, θE = 0.065 mas, implying that the lens system either has very low mass or lies much closer to the microlensed source than the Sun, or both. A Bayesian analysis yields component masses and source-lens distance , implying that this is a brown-dwarf/Jupiter system that probably lies in the Galactic bulge, a location that is also consistent with the relatively low lens-source relative proper motion = 3.2 0.5 mas yr−1. The projected companion-host separation is , indicating that the planet is placed beyond the snow line of the host, i.e., asl ∼ 0.12 au. Planet formation scenarios combined with the small companion-host mass ratio q ∼ 0.016 and separation suggest that the companion could be the first discovery of a giant planet that formed in a protoplanetary disk around a brown-dwarf host.
Summary
This systematic review was performed to compare the diagnostic accuracy of vertebral fracture assessment (VFA) with that of spinal radiography for identification of vertebral fractures (VFs). ...VFA appeared to have moderate sensitivity and high specificity for detecting VFs when compared with spinal radiography.
Introduction
VFs are recognized as the hallmark of osteoporosis, and a previous VF increases the risk of a future fracture. Therefore, the timely detection of VFs is important for prevention of further fractures. This systematic review examined the diagnostic accuracy of VFA using dual X-ray absorptiometry (DXA) to identify VFs.
Methods
We searched for potentially relevant studies using electronic databases, including Ovid-Medline, Ovid-EMBASE, Cochrane library, and four Korean databases, from their inception to May 2013. We compared the diagnostic accuracy of VFA with that of spinal radiography for detection of VFs by analyzing the sensitivity and specificity using a 2 × 2 contingency table. Subgroup analyses were also performed on studies with a low risk of bias and applicability.
Results
Twelve studies were analyzed for the diagnostic accuracy of VFA. The sensitivity and specificity were 0.70–0.93 and 0.95–1.00, respectively, analyzed on a per-vertebra basis, and 0.65–1.00 and 0.74–1.00 on a per-patient basis. The sensitivity and specificity of five studies in subgroups with a low risk of bias in the intervention test were 0.70–0.84 and 0.96–0.99, respectively. In studies with a low risk of bias in the patient selection, those based on a per-vertebra basis in three studies were 0.70–0.93 and 0.96–1.00, respectively.
Conclusions
VFA had moderate sensitivity and high specificity for detecting VF when compared with spinal radiography. However, the present findings are insufficient to assess whether spinal radiography should be replaced by VFA.
Aims/hypothesis
The unfolded protein response (UPR) in endoplasmic reticulum (ER) and autophagy are known to be related. We investigated the role of autophagy in UPR of pancreatic beta cells and the ...susceptibility of autophagy-deficient beta cells to the ER stress that is implicated in the development of diabetes.
Methods
Rat insulin promoter (RIP)-
Cre
+
;autophagy-related 7 (
Atg7
)
F/W
mice were bred with
ob/w
mice to derive RIP-
Cre
+
;
Atg7
F/F
-
ob/ob
mice and to induce ER stress in vivo.
GFP-LC3
+
-
ob/ob
mice were generated to examine in vivo autophagic activity. Real-time RT-PCR was performed to study the expression of the genes of the UPR machinery. Proteolysis was assessed by determining release of incorporated radioactive leucine.
Results
Production of UPR machinery was reduced in autophagy-deficient beta cells, which was associated with diminished production of p85α and p85β regulatory subunits of phosphoinositide 3-kinase. Because of compromised UPR machinery, autophagy-deficient beta cells were susceptible to ER stressors in vitro. When mice with beta cell-specific autophagy deficiency, which have mild hyperglycaemia, were bred with
ob/ob
mice to induce ER stress in vivo, severe diabetes developed, which was accompanied by an increase in beta cell death and accumulation of reactive oxygen species. The increased demand for UPR present in obesity was unmet in autophagy-deficient beta cells. Autophagy level and autophagic activity were enhanced by lipid, while proteolysis was reduced.
Conclusions/interpretation
These results suggest that autophagy is important for intact UPR machinery and appropriate UPR in response to lipid injury that increases demand for UPR. Autophagy deficiency in pancreatic beta cells may contribute to the progression from obesity to diabetes.
This review paper provides a recent overview of current international research that is being conducted into the functional properties of cellulose as a nanomaterial. A particular emphasis is placed ...on fundamental and applied research that is being undertaken to generate applications, which are now becoming a real prospect given the developments in the field over the last 20 years. A short introduction covers the context of the work, and definitions of the different forms of cellulose nanomaterials (CNMs) that are most widely studied. We also address the terminology used for CNMs, suggesting a standard way to classify these materials. The reviews are separated out into theme areas, namely healthcare, water purification, biocomposites, and energy. Each section contains a short review of the field within the theme and summarizes recent work being undertaken by the groups represented. Topics that are covered include cellulose nanocrystals for directed growth of tissues, bacterial cellulose in healthcare, nanocellulose for drug delivery, nanocellulose for water purification, nanocellulose for thermoplastic composites, nanocellulose for structurally colored materials, transparent wood biocomposites, supercapacitors and batteries.
Kondo screening in a Majorana metal Lee, S.; Choi, Y. S.; Do, S.-H. ...
Nature communications,
11/2023, Letnik:
14, Številka:
1
Journal Article
Recenzirano
Odprti dostop
Abstract
Kondo impurities provide a nontrivial probe to unravel the character of the excitations of a quantum spin liquid. In the
S
= 1/2 Kitaev model on the honeycomb lattice, Kondo impurities ...embedded in the spin-liquid host can be screened by itinerant Majorana fermions via gauge-flux binding. Here, we report experimental signatures of metallic-like Kondo screening at intermediate temperatures in the Kitaev honeycomb material
α
-RuCl
3
with dilute Cr
3+
(
S
= 3/2) impurities. The static magnetic susceptibility, the muon Knight shift, and the muon spin-relaxation rate all feature logarithmic divergences, a hallmark of a metallic Kondo effect. Concurrently, the linear coefficient of the magnetic specific heat is large in the same temperature regime, indicating the presence of a host Majorana metal. This observation opens new avenues for exploring uncharted Kondo physics in insulating quantum magnets.
The mechanism of primary resistance to epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors (TKIs) in EGFR-mutant non-small-cell lung cancer (NSCLC) has not been clearly understood.
...Eleven patients exhibiting primary resistance (disease progression <3 months) were identified among 197 consecutive NSCLC patients with TKI-sensitive EGFR mutations who received EGFR TKIs at Seoul National University Hospital. Treatment-naïve tumors were examined for concurrent genetic alterations using fluorescence in situ hybridization and targeted deep sequencing of cancer-related genes. Deletion polymorphism of Bcl-2-interacting mediator of cell death (BIM) gene was examined to validate its predictive role for TKI outcome.
The median progression-free survival (PFS) for patients receiving EGFR TKIs was 11.9 months, and the response rate 78.8%. Among the 11 patients exhibiting primary resistance, a de novo T790M mutation was identified in one patient, and two exhibited mesenchymal-epithelial transition amplification and anaplastic lymphoma kinase fusion. Targeted deep sequencing identified no recurrent, coexistent drivers of NSCLC. Survival analysis revealed that patients with recurrent disease after surgery had a longer PFS than those with initial stage IV disease. However, BIM deletion polymorphism, line of treatment, EGFR genotype, and smoking were not predictive of PFS for EGFR TKIs.
We identified coexistent genetic alterations of cancer-related genes that could explain primary resistance in a small proportion of patients. Our result suggests that the mechanism of primary resistance might be heterogeneous.
Background. Better understanding of complications and outcomes of adults hospitalized with respiratory syncytial virus (RSV) infection is necessary. Methods. A retrospective cohort study was ...conducted on all adults (≥18 years) admitted to 3 acute care general hospitals in Hong Kong with virologically confirmed RSV infection during 2009–2011 (N = 607). Adults hospitalized for seasonal influenza during the period were used for comparison (n = 547). Both infections were prospectively diagnosed following a standard protocol. Independent reviews of chest radiographs were performed by radiologists. Main outcome measures were all-cause death, respiratory failure requiring ventilatory support, and hospitalization duration. Cox proportional hazards models were used for analyses. Results. The mean age of RSV patients was 75 (SD, 16) years; 87% had underlying conditions. Lower respiratory and cardiovascular complications were diagnosed in 71.9% (pneumonia, 42.3%; acute bronchitis, 21.9%; chronic obstructive pulmonary disease/asthma exacerbation, 27.3%) and 14.3% of patients, respectively; 12.5% had bacterial superinfections. Supplemental oxygen and ventilatory support were required in 67.9% and 11.1%, respectively. Crude all-cause mortality was 9.1% and 11.9% within 30 days and 60 days, respectively; mean length of stay of survivors was 12 (SD, 13) days. Advanced age, radiographic pneumonia, requirement for ventilation, bacterial superinfection, and elevated urea level and white blood cell count were independently associated with poorer survival. Systemic corticosteroid use was associated with longer hospitalization and secondary infections. The overall outcomes of survival and length of stay were not significantly different from those in influenza. Conclusions. RSV can cause severe lower respiratory complications in older adults, resulting in respiratory failure, prolonged hospitalization, and high mortality similar to seasonal influenza. Corticosteroids did not seem to improve outcomes. The unmet need for antiviral therapy and vaccination against RSV in adults should be promptly addressed.
Current microlensing surveys are sensitive to free-floating planets down to Earth-mass objects. All published microlensing events attributed to unbound planets were identified based on their short ...timescale (below two days), but lacked an angular Einstein radius measurement (and hence lacked a significant constraint on the lens mass). Here, we present the discovery of a Neptune-mass free-floating planet candidate in the ultrashort (tE = 0.320 0.003 days) microlensing event OGLE-2016-BLG-1540. The event exhibited strong finite-source effects, which allowed us to measure its angular Einstein radius of θE = 9.2 0.5 as. There remains, however, a degeneracy between the lens mass and distance. The combination of the source proper motion and source-lens relative proper motion measurements favors a Neptune-mass lens located in the Galactic disk. However, we cannot rule out that the lens is a Saturn-mass object belonging to the bulge population. We exclude stellar companions up to ∼15 au.
In this randomized study of patients with upper gastrointestinal bleeding, infusion of omeprazole, as compared with placebo, before endoscopy reduced the incidence of endoscopic treatment (19.1% vs. ...28.4%, P=0.007) and, among patients with peptic ulcers, resulted in fewer actively bleeding ulcers and more ulcers with clean bases. These findings suggest that infused omeprazole is beneficial for patients with upper gastrointestinal bleeding who are awaiting endoscopy.
In patients with upper gastrointestinal bleeding, infusion of omeprazole before endoscopy reduced the incidence of endoscopic treatment (19.1% vs. 28.4%) and, among patients with peptic ulcers, resulted in fewer actively bleeding ulcers and more ulcers with clean bases.
In patients with bleeding peptic ulcers, we previously showed that infusion of a high-dose proton-pump inhibitor after hemostasis had been achieved during endoscopy reduced recurrent bleeding and improved clinical outcomes.
1
The adjuvant use of high-dose proton-pump inhibitors in endoscopic therapy has also been endorsed in two consensus statements
2
,
3
and confirmed in two meta-analyses.
4
,
5
Clot formation over arteries is pH dependent; a gastric pH above 6 is thought to be critical for platelet aggregation.
6
When given intravenously and at a high dose, proton-pump inhibitors can be used to maintain a neutral gastric pH.
7
In clinical practice, treatment with proton-pump . . .
Aim
To investigate the effects of LY2405319, an analogue of fibroblast growth factor 21 (FGF21), on glucose homeostasis in streptozotocin (STZ)‐induced insulin‐deficient mice (STZ mice).
Methods
...Nine‐week‐old male C57BL/6J mice were administered a single intraperitoneal injection of STZ (150 mg/kg). One week later, after confirmation of hyperglycaemia, saline or LY2405319 (5 mg/kg) was injected subcutaneously daily for 4 weeks. Changes in glucose homeostasis, energy metabolism and brown adipose tissue (BAT) function were assessed.
Results
The STZ mice had elevated blood glucose and reduced plasma FGF21 levels, impaired glucose uptake in the BAT, and BAT mitochondria with absent or swollen cristae and fewer lipid vacuoles. LY2405319 significantly reduced blood glucose levels and this was associated with increased BAT glucose uptake and changes in gene expression and morphology, indicating improved mitochondrial lipid metabolism in the BAT. Importantly, the ability of LY2405319 to lower blood glucose in STZ mice was compromised after removing interscapular BAT.
Conclusions
Our results show that LY2405319 reduces blood glucose levels in insulin‐deficient diabetes by improving BAT metabolism. Additional studies investigating the therapeutic potential of FGF21 for the treatment of type 1 diabetes are warranted.
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